A New Study Sketches a Terrifying, Near-Term Climate Future
Why its so difficult to talk about the new bombshell climate paper There has never before been a scientific study quite like the one released this week by James Hansen, a climate scientist and the former director of NASAs Goddard Institute for Space Studies. The paper, published Tuesday in Atmospheric Chemistry and Physics , reports that the near-term effects of climate change could be much more catastrophic than previously anticipated. It warns that, by 2100, the planets natural system could change so dramatically that enormous superstorms, sometimes powerful enough to hurl ocean boulders hundreds of feet into the air, will form in the Atlantic Ocean. Seas could also rise so quickly that they will inundate coastal citiesincluding New York, Washington, and San Franciscorendering them unlivable before the end of the century. Hansens paper isnt the first to spell out a scenario for climate doom. What makes it so harrowing, though, is that it says all these consequences would follow the global average temperature rising a relatively small amount: only two degrees Celsius. That isnt an arbitrary target. The nations of the world have repeatedly agreed to keep climate change specifically below two degrees Celsius, but, without as yet uninvented technology, it will be scientifically unlikely . If these terrifying conclusions sound familiar, its because they were first in the news last summer, when Hansen and his 18 co-authorsall climatologists, geologists, or academic scientists in their own rightreleased the paper online before it was peer reviewed. They said that the papers findings were too urgent, and the United Nations climate negotiations that December too imminent, to wait for the complete publication process. Given the inertia of the climate and energy systems, and the grave threat posed by continued high emissions, the matter is urgent and calls for emergency cooperation among nations, they wrote, in the papers conclusion. As such, the paper went through an unusually public review process. The New Yorker , Rolling Stone , and The New York Times all covered the study soon after its release . As other climatologists began to examine its findings, their criticisms made the Times and other newspapers again and again. This was not always a clean process, or a process where reporters could be sure they were publishing scientifically vetted information. Andrew Revkin, the Times writer who followed the public peer-review process from the beginning, has argued since last summer that the studys unusual method of well-publicized publication could lead to whiplash, at best, and confusion and disengagement at worst. As Revkin noted Tuesday , the peer-review process was not for naught: The final paper was altered, sometimes significantly, from its July 2015 draft. For example, while last years version of the paper claimed absolute certainty in its title Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 C global warming is highly dangerous this years final version scales that language back: Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 C global warming could be dangerous Now the paper has at last been peer reviewed and published. The Times and the Post both covered its release on Tuesday, the latter with the headline: We had all better hope these scientists are wrong about the planets future . And indeed, we had better. Hansen and his teams predictions are grave. They are out in public again, describing the potential consequences of their findings. Hansen himself posted a video explaining the science of the paper this week. If youre interested in climate change and the planet, its worth watching: He brings together his scientific conclusions with what he believes are the right political actions. At the heart of the findings is his argument that cold meltwater from Greenland is weakening an important internal current in the Atlantic Ocean, called AMOC , that keeps weather across the entire planet temperate. Once this current is shut down, then the Atlantic near the Arctic will stay cold and heat will build up in the southern latitudes, creating the potential for extreme weather of mythical proportions. I believe we are already watching the beginning of this cooling, southeast of Greenland, Hansen says. In that case, extra cooling and extra warming along the United States East Coast are not natural fluctuations. The warm water is the reason that [Hurricane] Sandy retained hurricane-force winds up to the New York City area. Have we passed a point of no return? I doubt it, but its conceivable, he adds. But if we wait until the real world reveals itself clearly, it may be too late to avoid sea-level rise of several meters and loss of all coastal cities. The haste that Hansen is calling for here feels like a major change in how experts talk about climate to the publica change perhaps as significant as Al Gores An Inconvenient Truth, 10 years old this May. Its in line with how the Syrian civil war has been increasingly tied to the consequences of climate change ; or the ways that public figuresincluding Miamis Republican mayor speak about global warming as a thing happening now instead of in the future. Hansen is trying to wage a public campaign on behalf of science, using scientific events as news pegs. I think that is indispensable, noble work. Its the work that Hansen left NASA to do . But as a public consumer of science, its important to recognize that this study represents just one scientific finding. Now that Hansens findings have been published, they will be tested and vetted and re-checked. Notably, they do not carry the imprimatur of, say, the UNs Intergovernmental Panel on Climate Change, which releases consensus reports about the best available science. In fact, that is part of the point: Hansen and his team believe theyve found mechanisms that more popular climate models, including those used by UN teams, dont take into account. As such, there is a public responsibility to communicate them clearly. If some of Hansens most ambitious arguments prove wrong, it will not invalidate the entire global-warming mechanism. It will not make the need to reduce fossil-fuel use any less dire. It will just mean that the near-term timeline looks somewhat different. So it was odd to see Slate s in-house meteorologist, Eric Holthaus, describe Hansens findings as pat, in a piece headlined James Hansens Bombshell Climate Warning Is Now Part of the Scientific Canon : The world Hansen and his colleagues describe reads like a sci-fi plot synopsisand its now officially part of the scientific canon (though peer review doesnt necessarily guarantee that a paper is infallible). If Hansen and his colleagues are correct, this paper is likely one of the most important scientific contributions in historyand a stark warning to world governments to speed up the transition to carbon-free energy. Hansens paper does read like science fictionin fact, more than one journalist has compared it to The Day After Tomorrow. But to describe it as officially part of the scientific canon is so overstated as to tend toward meaninglessness. Hansens paper is scary, ambitious, fascinating, wide-ranging, well-sourced, and very newsworthybut its just another peer-reviewed scientific paper. The peer review and publication process catches many errors, but it does not guarantee anything close to infallibility. (Consider the replication crisis now ripping through academic psychology : a controversy entirely about all the errors allowed to seep through peer review.) Right now, Hansens paper is exactly officially as much a part of the scientific canon as this paper on feminist glaciology or this more serious one on murderous prairie dogs . This is not to downplay Hansens findingstheir seriousness, their veracity, or their urgency. Its not to diminish the climate emergency, either. Talking about something so worrisome, with margins of error so large, on deadline, in public, is hard. I am not guiltless of sensationalizing climate news. Late last year, I cited a science-fiction writer and climate activist while covering a series of unusually warm storms over the Arctic. I implicitly framed him as someone with a claim to scientific expertise that he didnt have. But this is a new era in climate communications, one in which scientists will try to assert the necessity of action as much as politicians or activists. It is critical that, while giving researchers their prized place in the public sphere, we do not overstate or sensationalize their findings. As journalists, as people speaking in public, and as concerned and vulnerable participants in the Earth system, we owe it to each other to get this right.